in-and-in

American  

[in-uhnd-in, -uhn-] / ˈɪn əndˈɪn, -ən- /

adverb

1. repeatedly within the same family, strain, etc..

   to breed stock in-and-in.

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in-and-in British  

adjective

1. (of breeding) carried out repeatedly among closely related individuals of the same species to eliminate or intensify certain characteristics

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Etymology

Origin of in-and-in

First recorded in 1620–30

Example Sentences

Breeding in-and-in, or propagating from animals nearly allied, may be tolerated under certain circumstances, though seldom; and only in extreme cases between those of the same generation, as brother and sister.

From Domestic Animals History and description of the horse, mule, cattle, sheep, swine, poultry and farm dogs; with directions for their management, breeding, crossing, rearing, feeding, and preparation for a profitable market; also their diseases and remedies. Together with full directions for the management of the dairy. by Allen, Richard L.

Time flies, but sin breeds in-and-in,   And a father's grief is stern; Robin is dead, and a distant kin   Now calls himself Kildearn.

From Wilson's Tales of the Borders and of Scotland, Volume XXIV. by Leighton, Alexander

Few domesticated animals suffer so much from in-and-in breeding as swine.

From Sheep, Swine, and Poultry Embracing the History and Varieties of Each; The Best Modes of Breeding; Their Feeding and Management; Together with etc. by Jennings, Robert

In the latter case breeding in-and-in is usually found to result in decided and rapid deterioration.

From The Principles of Breeding or, Glimpses at the Physiological Laws involved in the Reproduction and Improvement of Domestic Animals by Goodale, S. L.

But variations here, as elsewhere, would naturally present themselves; and those of our ancestors who avoided in-and-in breeding would survive, while the others would gradually decay and ultimately perish.

From The Tribes and Castes of the Central Provinces of India—Volume I (of IV) by Russell, R. V. (Robert Vane)